CRYSTAL QUARTZ WOLLASTON / ROCHON

Crystal quartz Wollaston and Rochon polarizers are made of two prisms of crystal quartz which are cemented for use from 350 nm to about 2700 nm. These types of polarizers are used for applications where small beam separations are required. The largest beam separations available in standard crystal quartz Wollastons and Rochons are 2 degrees and 1 degree respectively. Smaller beam separations are available on special order. Beam separation is dependent on wavelength. In a Rochon, one of the prisms needs to have it's optic axis perpendicular to the entrance face. Because of optical activity in crystal quartz, the incident beam should first traverse this component. The arrow marked on its mount indicates the required beam direction in the crystal quartz Rochon. In the case of the Wollaston, either of the two polished ends can be used as the entrance face of the polarizer. Crystal quartz polarizers have an extinction ratio of at least 10^-3.